Repentance in Chinese is comprised of two concepts: To “confess”
and to "not do it again”. Is to take the plant and remove the roots, not even allowing a thought to survive enough time to become anything more than a passing cloud.
"The Platform Sutra" - Sutra spoken by the Sixth Patriarch -From Chapter VI. On Repentance
I have a 'Formless' stanza, the reciting and practicing of which will
at once dispel the delusions and expiate the sins accumulated in numerous
Kalpas. This is the stanza:
People under delusion accumulate tainted merits but do not
tread the Path.
They are under the impression that to accumulate merits and to tread
the Path are one and the same thing.
Though their merits for alms-giving and offerings are infinite,
(They do not realize that) the ultimate source of sin lies in the three
poisonous elements (i.e., greed, anger and illusion) within their
own mind.
They expect to expiate their sins by accumulating merit
Without knowing that felicities obtained in future lives have nothing
to do with the expiation of sins.
Why not get rid of the sin within our own mind,
For this is true repentance (within our Essence of Mind)?
(A sinner) who realizes suddenly what constitutes true repentance according
to the Mahayana School,
And who ceases from doing evil and practices righteousness is free from
sin.
A treader of the Path who keeps a constant watch on his Essence of Mind
May be classified in the same group as the various Buddhas.
Our Patriarchs transmitted no other system of Law but this 'Sudden'
one.
May all followers of it see face to face their Essence of Mind and be
at once with the Buddhas.
If you are going to look for Dharmakaya
See it above Dharmalaksana (phenomena), and then your Mind will be pure.
Exert yourself in order to see face to face the Essence of Mind and
relax not,
For death may come suddenly and put an abrupt end to your earthly existence.
Those who understand the Mahayana teaching and are thus able to realize
the Essence of Mind
Should reverently put their palms together (as a sign of respect) and
fervently seek for the Dharmakaya.
The Patriarch then added:
practice. Should you realize your Essence of Mind after reciting it,
you may consider yourself to be always in my presence, though actually
you are a thousand miles away, but should you be unable to do so, then,
though we are face to face, we are really a thousand miles apart. In that
case, what is the use of taking the trouble to come here from so far away?
Take good care of yourselves. Good-bye.
The whole assembly, after hearing what the Patriarch had said, became
enlightened. In a very happy mood, they accepted his teaching and put it
into practice.
Source